Ynsats writes "The Register is reporting that SGI is filing suit against ATI for patent infringement. The suit alleges that ATI violated patent number 6,650,327, "Display system having floating point rasterization and floating point framebuffering", which was filed in 1998 and granted in 2003, in its Radeon graphics cards. This is coming fast on the heels of AMD's announcement of the intention to buy ATI for $4.2B and it doesn't seem to be swaying AMD's intentions. AMD hopes to finish the takeover by the end of this year. SGI has also issued an ominous statement stating that they have plenty of intellectual property left and there will be more litigation to come."